It's an artistic vision of a world where we do not know the possible far-reaching consequences of our actions, which may transcend our individual lives and ripple across centuries to form a grander pattern. The limitedness of a singular life covets a moral justification, and other than the bland idea of heaven and hell, a Cloud Atlas sort of karmic recurrence is of some possible consolation.

Skepticism kicks in soon after, bringing with it the despair of a world that has no plan in it, but if you are lucky the film would have done it's job of stretching your imagination enough that your whole existence quivers with the unheard symphonies of infinite possibilities.